Chuck.



J. HARTNESS.

CHUCK.

APPLICATION FILED PEB.20, 1913.

Patented Dec. 30, 1913.

2 SHEETSSHEET 1.

J. HARTNESS.

. CHUCK.

APPLICATION FILED rmmo, 191s.

Patented Dec. 30, 1913.

2 SHEETS-SHEET 2.

COLUMBIA PLANOGRAPH CO.,WASHINOTON. D. c.

JAMES HARTNESS, OF SPRINGFIELD, VERMONT.

CHUCK.

Specification of Letters Patent.

Patented Dec. 30, 1913.

Application filed February 20, 1913. Serial No. 749,631.

To all whom it may concern Be it known that I, J AMES HARrNnss, acitizen of the United States, and a resident of Springfield, in thecounty of "Windsor and State of Vermont, have invented certain new anduseful Improvements in Chucks, of which the following is aspecification.

This invention has relation to chucks and more particularly to scrollchucks, socalled, in which the radially movable jaws are moved inguideways in the body of the chuck by a scroll engaging one or moreteeth or projections in the rear portions of the aws.

The invention consists in constructing the body in sections so spacedapart as to form equally spaced guideways for the jaws. These sectionsare approximately sectorshaped and may be adjusted so as to provide fora varying number of jaws, so that, if desired, a chuck may be equippedwith three jaws or with four jaws according to the character of the workto be operated on, or according to the desire of the operator.

In furnishing a chuck, there are provided a plurality of body sectionsand a plurality of spacers. The sections are made in pairs and eachsection of the pair is formed on its outer side to constitute one wallof a guideway for the jaw, so that, when two adjacent sections of twopairs are properly placed and spaced apart, they form a guideway betweenthem in which the aw may be operated by the scroll.

Referring to the accompanying drawings, Figure 1 represents a frontelevation of a chuck embodying the invention, provided with four jaws.Fig. 2 represents a section on the line 2-2 of Fig. 1. Fig. 3 representsa side elevation of the chuck. Fig. represents a section on the line Hof 1. Fig. 5 represents a section on the l1ne 55 of Fig. 1. Fig. 6 showsone of the body sections detached. Fig. 7 represents a front elevationof the same chuck arranged to receive three jaws. Fig. 8 represents asection on the line 88 of Fig. 7. Fig. 9 shows a front elevation of thechuck with the body removed. Fig. 10 represents a section on the linel010 of Fig. 8. Fig. 11 represents a side elevation of the chuck. Fig.12 represents one of the spacers detached.

Referring to the drawings,20 indicates the back-plate of the chuck whichis formed with a hub 21 internallythreaded so as to screw upon the endof a hollow spindle 22.

This back-plate might, if desired, be formed integrally with thespindle. In the face of the back-plate, there is an annular groove 23 toreceive the jaw-operating scroll 24. Loosely mounted on the hub 21 ofthe backplate, there is a gear-operating scroll 25 having a rearwardlyextending marginal flange 26 formed by cutting a groove 27. A.clamp-brake, such as illustrated in my copending application Serial No.722,962, filed September 28, 1912, may be used to clamp the flange 26and hold the scroll 25 against rotation. Preferably the back-plate andthe rear scroll 25 are equal in external diameter. The back-plate 20serves as a support for one or more spiral gears 28 (see Fig. 9). Theaxes of these gears are tangential to a circle circumscribed about theaxis of the back-plate and they are preferably equidistant as shown. Thesaid gears are loosely mounted on smooth portions of screw pins 29 whichare passed into sockets formed in the back-plate, the gears themselvesbeing located in recesses extending through the web of the back-plate asshown in Fig. 5. The arrangement of the gears is such that theyintermesh with the scroll teeth 30 formed on the front face of the rearscroll 25, and also intermesh with rack teeth 31 formed on the rear faceof the aw-operat-ing scroll 24. Nhen the chuck is quiescent, therotation of the rear scroll causes the rotation of the jaw-operatingscroll (and the actuation of the jaws) through the medium of theinterposed ower-transmitting mechanism, which in t is case consists ofone or more of the spiral gears 28. When the chuck is in rotation, therear scroll may be retarded so as to cause a similar movement of thejaw-operating scroll. Ordinarily the back-plate and the scroll 25 rotatein unison. The rear scroll is held against axial movement by a collar 32detachably secured by any suitable means such as a screw 38 and pin 34:to the hub 21 of the back-plate. In general, the parts which I havedescribed correspond to those which are illustrated in my application towhich I have previously made reference.

The body of the chuck in the present case consists of a plurality ofsections which may be located in various positions to form guideways forvarious numbers of jaws. In Fig. 1, there are four jaws which areindicated at 40, 41, 42 and 43. In this case, i

usual shoulders as shown in Figs. 2 and 8.

The parallel side faces of each jaw are formed with tongues and groovesas shown in Figs. 3, 4L and 11.

In Fig. 1, the body of the chuck is shown as comprising eight sectionsa, b, 0, (Z, 6, f, g and it. They are arranged in pairs at Z), 0 (Z,etc., the inner faces of the sections of each pair abutting and theouter faces of the sections of each pair being provided with tongues andgrooves complemental to those formed in the jaws. In Fig. l, the fourpairs of sections are arranged to provide for radial grooves to receivethe four jaws. Each section is secured to the rear plate by a pluralityof screws or like fastenings. Viewed in front elevation, the screws arearranged in two circles, one series of screws being located near theouter margins of the sections and the other screws being located neartheir inner ends. There are two of the outer screws 44 and one innerscrew 45 for each section. For the purpose of enabling an adjustment'ofthe sections to provide for a smaller number of jaws, I furnish witheach chuck a plurality of spacers 7c, of which one is shown in Fig. 12.Each spacer is adapted to be placed between the sections of a pair ofsections so as to spread them apart. The side faces of each spacer areat approximately an angle of 80, so that, when a. spacer is placedbetween the sections of a pair, the outer faces of the pair will bechanged from an angle of 90 to an angle of 120, thus making provisionfor the employment of only three jaws instead of four. For the purposeof changing over the chuck from four jaws to three jaws, all of thesections shown in Fig. 1 are removed except those indicated at a and 71Then two spacers 7c are secured in place adjacent the remaining sectionsa and h. Then the two sections 6 and g are neXt secured in place in thepositions shown in Fig. 7 The sections a and d, with the spacer isbetween them, are then secured to the back-plate, so that as a resultthree radial guideways are provided for the three jaws 40, ll and .12.Thus the two sections 0 f and the jaw i3 are temporarily laid asideuntil it is desired to transform the chuck again into a four-j awedchuck. The back-plate is provided with a proper number of properlyspaced apertures to receive the fastening screws 44 and 45 for thesections and also with apertures to receive fastening screws 46 and a7which secure the spacers to the back-plate.

So far as I am aware, I am the first to have provided a chuck comprisinga back plate and a body formed of a plurality of sections adjustable toform a varying number of guideways for the jaws. I might, of course,omit the section spacers altogether, but I prefer to use them as theystiffen the body and hold the sections of each pair rigidly in theirproper positions.

Having thus explained the nature of my said invention and described away of making and using the same, although withoutattempting to setforth all of the forms in which it may be made or all of the modes ofits use, what I claim is:

1. A scroll chuck comprising a jaw-operating scroll, a plurality ofradial jaws, a back-plate, and a body consisting of a plurality ofsections secured to said back-plate, said sections being spaced to formguideways for said jaws.

2. A scroll chuck comprising a plurality of radial jaws, a jaw-operatingscroll, a back-plate, and a body attached to the backplate andconsisting of a plurality of pairs of sections, said pairs beingseparated to form guid-eways for the jaws.

3. A scroll chuck comprising a plurality of radial jaws, a jaw-operatingscroll, a backplate, and a body attached to the back-plate andconsisting of a plurality of sections, said sections being adjustable toprovide a varying number of equally spaced guideways for receiving anequal number of jaws.

t. A scroll chuck comprising a jaw-operating scroll, and a back-plate,of a plurality of radial jaws, and a detachable body, said bodyconsisting of a plurality of pairs of sections separated to formguideways for the jaws, and secured independently of each other .to theback-plate.

5. A chuck comprising a back-plate, jawoperating mechanism, a pluralityof jaws, a body consisting of a plurality of adjustable sector-shapedsections spaced to form guideways for the jaws, said back-plate havingprovisions for receiving a variable number of sections to accommodate avariable number of jaws.

6. A chuck comprising a back-plate, jawoperating mechanism, and a bodyconsisting of a series of independent sections spaced to form radialguideways for the jaws, said sections being adapted to be adjusted to*ary the number of such guideways, and means for securing said sectionsto the backplate in the positions to which they may be adjusted.

7. A chuck comprising a back-plate and a sectional body detachablysecured thereto, the sections being adapted to be equally spaced indifferent positions to receive either three or four jaws.

8. A chuck comprising a back-plate, a jaw-operating scroll, and a bodyconsisting of a series of pairs of detachable sectorshaped sectionsspaced apart to form radial jaw-receiving gnideways, and a. sectorshapedspacer between the sections of each pair, said spacers being removable,the sections of said pair being adapted to be closed together, and saidpairs to be adjusted,

whereby space is made for an additional 10 pair of sections, and for anadditional guide- Way for an additional jaw.

In testimony whereof I have aflixed my signature, in presence of twoWitnesses.

. JAMES HARTNESS. Witnesses:

RALPH E. FLANDnRs,

J. W. WALKER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of latents. Washington, D. 0.

